Water-borne pathogens are disease-causing bacteria, viruses, and protozoa you can get from impure water. Protozoa are hard-shelled, single-cell parasites, or cysts, that range from 2 to 15 microns in size. The giardia lamblia cyst is one of the most common water-borne parasites in the United States. Cryptosporidium is also a protozoa, and cryptosporidiosis exhibits symptoms similar to giardiasis, including diarrhea, Read More